es-module-traversal

Gather all imported files from some ES modules entrypoints,

You can also customize the resolver and read functions to traverse the import graph from a static server

``
npm install es-module-traversal
`

Benchmarks

Run the benchmarks with the yarn test:bench command

It traverses the graph of 780 modules in about 0.30 seconds, most of the time is spent by es-module-lexer (this means that the time will increase with the size of the javascript modules)

It takes about 5 seconds to traverse the graph of a big typescript app with 3900 files of 30 lines each, the overhead here is given by the time vite takes to transform the typescript files

Example

`ts
import path from 'path'
import { traverseEsModules } from 'es-module-traversal'

const res = await traverseEsModules({
entryPoints: [path.resolve(__dirname, __filename)],
onEntry: (path) => {
console.log('traversed ' + path)
},
})

console.log(res)
// [{
// importPath: './someImport',
// resolvedImportPath: '/path/to/file',
// importer: '/path/to/importer'
// }, ...]
`

Fetching from a static server

`ts
// customize resolution to use a server instead of disk
import path from 'path'
import {
traverseEsModules,
urlResolver,
readFromUrlOrPath,
} from 'es-module-traversal'

const port = '3000'
const res = await traverseEsModules({
entryPoint: http://localhost:${port}/main.tsx,
// like require.resolve but support urls and paths
resolver: urlResolver({
root: __dirname,
baseUrl: http://localhost:${port}/,
}),
onEntry: (path) => {
console.log('traversed ' + path)
},
})
console.log(JSON.stringify(res, null, 4))

// [
// {
// importPath: '/firstLevel.js',
// importer: 'http://localhost:9000/deep/file.js',
// resolvedImportPath: 'http://localhost:9000/firstLevel.js',
// },
// ...
// ]
``